In order to extract the faint fault information from complicated vibration signal of bearing, the correlated kurtosis is introduced into the field of rolling bearing fault diagnosis. Combined with SVD and correlated kurtosis, a feature extraction method is proposed. According to the method, by SVD processing a group of component signals are obtained, then the component signals with equal correlated kurtosis are selected to be added together, and the weak fault signal is clearly extracted. The effectiveness of the method is demonstrated on both simulated signal and actual data.